Project Description-Summary The overall goals of the Collaboration and Service Core (C&S) are to provide non-specialists with access to MS technologies, software, methods, technical expertise and support developed in the Washington University (WU) Biomedical Mass Spectrometry (MS) Resource, and to provide experienced investigators with shared access to MS instrumentation and software so they can independently conduct sample analyses. Requests for C&S projects are evaluated by the Operational Team and selected based on established criteria. Completed, ongoing, and new C&S projects are evaluated for impact based on publications/productivity; tracked to document efficient MS instrument utilization; and monitored to insure that MS Resources are shared equitably with WU and outside users who acknowledge the contributions of the WU Biomedical MS Resource and comply with NIH public access policies.